Air bag module including improved inflator retainer assembly

ABSTRACT

An air bag module ( 20 ) including: an inflator ( 200 ) for providing inflation gas; a bracket assembly ( 100 ) having an integral spring portion for resiliently biasing the inflator toward a retained position.

This application claims the benefit of U.S. Provisional Application60/654,220, filed on Feb. 18, 2005. The disclosure of the aboveapplication is incorporated herein by reference.

BACKGROUND AND SUMMARY OF THE INVENTION

The present invention relates generally to air bags and moreparticularly to an improved apparatus and methodology for fabricatingand assembling an air bag module.

The illustrated embodiment of the invention identifies a side air bagmodule; however, the present invention can be implemented with othertypes of air bag modules, such as curtain, passenger and driver.

It is an object of the present invention to provide an air bag modulehaving fewer parts and an improved bracket with a reactive orspring-like portion.

Accordingly the invention comprises: an air bag module 20 comprising: aninflator 200 for providing inflation gas; a bracket assembly 100comprising an integral spring portion for resiliently biasing theinflator toward a retained position.

Many other objects and purposes of the invention will be clear from thefollowing detailed description of the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates two of the major components of an air bag moduleutilizing the present invention.

FIG. 2 is an isometric view of a bracket assembly.

FIG. 2 a is an end view of the bracket assembly of FIG. 2.

FIG. 3 illustrates the inflator partially received within the bracketassembly.

FIG. 4 is an isometric, end view illustrating the condition of theinflator corresponding with that of FIG. 3.

FIG. 5 is an isometric view showing the inflator fully assembled to thebracket assembly.

FIG. 6 is a cross-sectional view of a side impact air bag moduleconstructed in accordance with the invention.

FIG. 7 illustrates the air bag module of FIG. 6 installed in a vehicleseat and configured as a side impact air bag module.

FIG. 8 illustrates an alternate embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

Reference is made to FIG. 1, which illustrates two of the majorcomponents of an air bag module 20 made in accordance with the presentinvention. The air bag module 20 comprises a retainer or bracketassembly 100, an inflator 200, and an air bag 300 shown in FIG. 6. Theair bag 300, once configured in a rolled or folded condition, ismaintained in this condition by a thin wrapping 310, also shown in FIG.6. In certain installations, as known in the art, the air bag module mayalso include a cover about the thin wrapping for protecting the storedor folded air bag and inflator.

Returning to FIG. 1, the bracket assembly (also referred to as theretainer assembly) comprises a stamped, preferably steel bracket ormember 102, having a central, elongated plate portion or plate 104,generally located in the middle of the bracket assembly. The bracket 102transitions into opposingly situated upraised sides 106 a and 106 bparallel to a longitudinal axis 112 through the plate portion 104. Thesides 106 a and 106 b are optional as illustrated in the alternateembodiment shown in FIG. 8.

The plate 104 includes a plurality of mounting openings 107 a,b shown inFIG. 2. Each opening receives a respective threaded mounting stud 110;each stud is adapted to be secured to a frame portion within thevehicle. The bracket assembly 100 includes two opposed ends 120 and 130,respectively. The plate portion 104, as shown in FIG. 2, includes astamped feature in the form of a tab 109. The tab is used to identifybrackets to be used on left or right-hand vehicle seats or other similarmounting locations. For example, in some brackets the tab 109 is bentdown as illustrated in FIG. 2; in other brackets the tab is formed butnot bent, or not formed at all.

End 120 is integrally formed as a one-piece component with plate portion104 and includes a first inflator-receiving opening 122. The lowerextreme 124 of the opening is spaced a distance d1 from the top of theplate 102, which is helpful in orienting and positioning the inflator.During fabricating of the bracket assembly, end 120 is bent upwardly(from its initial planar configuration) by an angle A1 degrees (seeFIG. 1) from the plane 112 of the plate 104, as illustrated in thefigures. Opening 122 is preferably circular in shape, but in general theshape of opening 122 will conform to the shape of a mating part of theinflator or at least permit passage of this mating part therethrough. Inthe preferred embodiment of the invention the end 120 is bent upwardlyby about 85 degrees (A1=85 degrees).

End 130 is also integrally formed as part of the plate 104 with end 120,and comprises an oblong shaped rim 129 having an oblong opening 132. Thebottom 134 of opening 132 is spaced a distance d2 from the plate 104 toposition and orient the inflator. End 130 is bent upwardly from theplane of plate 104 by an angle of A2. In the preferred embodiment angleA2 is approximately 35 degrees.

As illustrated in FIGS. 2 and 2 a, the oblong opening 132 includes amajor diameter 140 and a minor diameter 142. Reference is briefly madeto FIG. 1 and more particularly to the inflator 200. As can be seen, theinflator is generally cylindrical in shape and includes a major bodyportion 202, which is circular in diameter. The diameter of the bodyportion 202 is slightly smaller than the minor diameter 142 to permitpassage of the inflator within opening 132.

As illustrated, the inflator 200 is a stored-gas inflator, whichincludes a gas, air, argon or helium or any combination thereof and apyrotechnic element or elements, which include at least one initiator211 that is capable of initiating the release of the stored gas orheating the stored gas prior to exiting a plurality of exit ports 210.The initiator receives an activation signal from an associatedcontroller (not shown). The inflator includes a cylindrically shapedmounting end 212 (which houses the initiator 211 and the initiator'selectrical connector 213, see FIG. 8), which is insertable throughopening 122 of the bracket assembly 100. In the preferred embodiment,the diameter of end 212 is slightly smaller than the diameter of opening122.

Reference is now made to FIG. 3, which illustrates the inflator 200 in apartially assembled configuration relative to the retainer assembly 100.In this configuration the large end 206 of the inflator has beeninserted within opening 132 of bracket end 130. In this configuration,in view of the fact the minor diameter of opening 130 is generallylarger than the outside diameter 206 of the body 202, the inflator iseasily inserted within the opening. With the inflator 200 partiallyinserted within opening 132, the lower side or bottom 222 of theinflator 200 engages the lower extremes 146 or bottom 134 of opening132, which provides an effective pivot point about which the inflatorwill rotate. As the inflator 200 is positioned in opening 132, the plate104 of the bracket is maintained in a generally horizontal orientation.

The inflator 200 will seek a stable angular orientation, as it willrotate about the pivot point until the upper side or top 220 of theinflator engages the top or apex 144 of opening 132, at which time theinflator 200 will be oriented at an angle A3 relative to the plate 104.Thereafter the end 212 of the inflator 200 is pushed into contact withthe inner side or face 126 of bracket end 120, as shown in FIG. 3. AngleA3 is proportional to the relative size of the major diameter 144 andthe diameter of the inflator. For example, the angle A3 will decreasewith increasing major diameters. As can be seen in FIG. 3, in theabove-described configuration, end 212 of the inflator 200 is positionedadjacent the inner side 126 of end 120. In the intermediaryconfiguration the geometric center of the circular end 212 is slightlyabove the geometric center of circular opening 122.

With the inflator and bracket in the condition as described in FIG. 3,the inflator 200 is rotated downwardly relative to the plate 104 of thebracket assembly while the inflator remains in the opening 132. As theinflator is rotated, it remains in contact with the bracket 100 at thetop or apex 144 of opening 132, as well as at the bottom or nadir 134 ofopening 132. The sharp edges of the bracket 100 about the opening 132hold the inflator 200 in place.

Reference is briefly made to FIG. 4, which is an end-isometric view ofthe partially assembled inflator/retainer assembly of FIG. 3. Therelationship between the size of the body 202 and opening 132 can beseen more clearly in this FIG. 4.

To complete the assembly of the inflator 200 to the retainer assembly orbracket 100, the inflator 200 is forcibly rotated downwardly asillustrated by arrow 220, of FIG. 3, positioning end 212 in alignmentwith opening 122. As the inflator rotates, the inflator will bend orrotate bracket end 130 about an axis 150. As the bracket end 130rotates, it retains its elastic characteristics and acts as a spring,generating upon the inflator a bias, or twisting force in the directionof arrow 160 (see FIGS. 3 and 4) opposite to the direction of rotation.As can also be appreciated, end 130 is configured as an integral springsteel portion of the bracket assembly. Additionally, as the inflator isrotated, end 212 of the inflator 220 slides upon face 126 of the bracketend 120, pushing this bracket end outwardly (the opposite end of theinflator being retained in opening 132), see numeral 120 a FIG. 5. Whenthe inflator end 212 is in alignment with the opening 122, the inflatorend 212 snaps into opening 122 of the bracket end 120, which returns toits initial orientation. Thereafter the inflator is forcibly moved tothe right as illustrated in FIG. 3 so end 212 moves through opening 122until the enlarged portion 214 of the inflator becomes butted againstthe inner side or face 126 of bracket end 120.

Additionally, the spring force created by the bending of bracket end 130is sufficient to prevent the inflator from moving in and out relative tothe bracket in an axial direction. However, if desired, an additionalsnap ring or retainer can be inserted upon the extending end portion ofend 212 and pushed inwardly until it engages the outer side 160 ofbracket end 120. Such a spring retainer 250 is shown in FIG. 8. Thespring retainer has a plurality of spring fingers 252 fitted to theextending portion of end 212.

Reference is briefly made to FIG. 6, which is a cross-sectional viewshowing a portion of the retainer or bracket assembly 100 and inflator200 with one of the mounting fasteners 110 extending through the plateportion 104 of the bracket assembly. FIG. 6 also illustrates theassembled module 20. The module, as mentioned above, additionallyincludes an air bag 300. In the illustrated embodiment the air bag,which is of conventional construction, includes an opening or neckportion 302 into which the inflator-bracket subassembly has beeninserted. Thereafter, the opposing flaps 310 and 312 of the air bag 300are positioned upon the mounting studs 110 with each mounting stud 110entering and passing through a respective opening in each of the flaps310 and 312. Thereafter, the air bag is configured into a compactpre-inflation configuration, such as being rolled or folded or acombination thereof. This compact configuration is maintained in a knownmanner by enveloping the folded air bag with a breakable, protectivecovering 350. The covering is typically manufactured of a Tyvek or apaper-like material having a plurality of perforations 352, which areruptured upon inflation of the air bag. In certain installations, thecovering 350 can be enveloped by a breakable thicker plastic cover (notshown).

Reference is briefly made to FIG. 7, which illustrates the module 20installed on a section of a frame 402 of a portion of the vehicle. Inthe preferred embodiment, this frame 402 is an outside frame section ofa vehicle seat 404. The outside frame section is adjacent, for example,a vehicle door 406. The air bag module 20 is further encapsulated withinthe seat upholstery 410, which is often of a multi-layered construction.The upholstery typically will include a weakened point, region or areagenerally designated as 412, which is ruptured as the air bag inflates,thereby providing a channel or guide for the inflating air bag, theinflated air bag being shown by phantom line 300 a. In operation, onceassociated sensors of the vehicle sense an actual or impendingcollision, an activation signal is sent to the igniter 211 of theinflator 200, which provides the supply or the generation of inflationgas, which is communicated to the air bag through inflator ports 210.The air bag is subsequently inflated, rupturing the protectiveenveloping covering 350 as well as the seat cushion upholstery 410.

FIG. 8 shows an alternate embodiment of the invention. The bracket 100 ahas a flat plate portion 104 (without upraised edges) and an end 120 toreceive end 212 of the inflator and to support snap ring 250. Thebracket 100 a includes an opposite bracket end 130 a having an inflatorreceiving opening 132. Bracket end 130 a is formed as an integral partof the bracket 100 a and is bent upwardly from the plate 104 to a fixedposition and orientation. Opening 132 is larger than the diameter of theinflator as in the case with the earlier embodiment. In this embodimentend 130 a serves to hold the inflator 200 in place but does not providea spring function. The spring function is provided by a spring formed asan extending part, lever or spring tab 114 portion of plate 104.Initially, end 114 a of tab 114 is configured to be above the plane ofthe plate 104 to interfere with the inflator as the inflator 200 isinserted within opening 132. The spring or spring tab 114 urges theinflator 200 against the top region 133 of opening 132.

Many changes and modifications in the above-described embodiment of theinvention can, of course, be carried out without departing from thescope thereof. Accordingly, that scope is intended to be limited only bythe scope of the appended claims.

1. An air bag module (20) comprising: an inflator (200) for providinginflation gas; a retainer or bracket assembly (100) having a centralplate portion, a flexible first bracket end (120) oriented at anon-perpendicular angle relative to a plane of the central plate portionand a flexible, second bracket end (130) oriented at an initial firstnon-perpendicular predetermined angle relative to the plane of thecentral plate portion, and a portion of the second bracket endconfigured as a spring and being deformable by movement of the inflatorinto a retained position of the inflator, the inflator when in aninstalled position extending across and through the first and secondbracket ends, with portions of the inflator located on opposing sides ofeach of the first and second bracket ends; and the second bracket endconfigured to create a twisting force upon that portion of the inflatorextending through the second bracket end as a result of the secondbracket end being deformed.
 2. The module according to claim 1 whereinthe first bracket end (120) includes a first opening and wherein thesecond bracket end (130) includes a second opening and wherein thatportion of the inflator insertable into the second opening is smallerthan the second opening.
 3. The module according to claim 2 wherein thesecond bracket end is configured to engage the inflator near a top and abottom of the second opening as the inflator is moved to the retainedposition and to be bent as the inflator is so positioned.
 4. A method ofassembling an air bag module according to claim 1 comprising the stepsof: a) inserting the inflator through the second bracket end of thebracket assembly; b) rotating the inflator to a preferred positionrelative to the bracket assembly and while rotating the inflator,bending the second bracket end of the bracket assembly creating thetwisting force on the inflator.
 5. The method of claim 4 including thestep of inserting the inflator into the first bracket end of the bracketassembly.
 6. An air bag module (20) comprising: a cylindrically shapedinflator (200) for providing inflation gas to an air bag (300); abracket assembly (100) for receiving, holding and orienting the inflatorcomprising a first retaining bracket (120) having opposing sides and afirst opening (122) configured to receive a complementary shaped portionof the inflator and an opposing second retaining bracket (130), thesecond retaining bracket having opposing sides, and the inflatorconfigured to extend completely through both the first and the secondretaining brackets with portions of the inflator positioned adjacenteach opposing side of the first and second retaining brackets; and thesecond retaining bracket bent by the operation of the inflator, thesecond retaining bracket further configured to provide a twisting forceupon the inflator in reaction to being bent, urging the inflator intoportions of the first retaining bracket about the first opening, thesecond retaining bracket being the only retaining bracket providing atwisting force.
 7. The module according to claim 6 wherein the bracketassembly includes a center portion between the first and secondretaining brackets, and wherein the second retaining bracket isinitially oriented at a predetermined angle relative to the centerportion and bent inwardly toward the center portion by operation of theinflator.
 8. The module according to claim 7 wherein the first retainingbracket is configured to bend outwardly from an initial configurationupon receipt of the inflator and upon receipt of the inflator in thefirst opening to return to the initial configuration.
 9. The moduleaccording to claim 7 wherein the second retaining bracket extends awayfrom the center portion at an angle of about 85 degrees.
 10. The moduleaccording to claim 7 wherein the first retaining bracket extends awayfrom the center portion at an angle of about 95 degrees.
 11. The moduleaccording to claim 6 wherein the second retaining bracket is configuredto apply a twisting load to the inflator.
 12. An air bag modulecomprising: a retainer or bracket assembly comprising a center portionand a first retainer end portion and a second retainer end portion, eachof the first and second retainer end portions disposed generally atopposing ends of the center portion and in general alignment with oneanother, the first retainer end portion includes a first opening and thesecond retainer end portion includes a second opening, each of the firstand second openings configured to receive and retain a respective firstinflator end and an elongated body portion of an air bag inflator, theinflator crossing both the first and the second retainer end portions,the second retainer end portion further configured to be bent by theinflator as the inflator is twisted into a mounted position and thesecond retainer end portion generating a twisting bias retaining forceon the inflator, the force directed opposite to the direction the secondretainer end portion is bent, the force urging the first inflator endinto a portion of the first retainer end portion.
 13. The moduleaccording to claim 12 wherein the second retainer end portion, prior tobeing bent, is generally planar in shape and extends away from thecenter portion of the bracket assembly along a predetermined obtuseangle.
 14. The module according to claim 13 wherein the inflatorincludes the elongated body portion having a cylindrical shapereceivable into and through the second retainer end portion.
 15. Themodule according to claim 14 wherein the second opening is oblong inshape and includes a first diameter generally perpendicular to a seconddiameter, the first diameter being longer than the second diameter. 16.The module according to claim 12 wherein the second opening of thesecond retainer end portion is configured to permit the inflator to bemoved through the second opening and wherein the second retainer endportion is configured to act as a pivot to enable the inflator to moveabout the pivot and rotate within the second opening.
 17. The moduleaccording to claim 12 including a fastener secured to the first inflatorend, located proximate an exterior surface of the first retainer endportion.
 18. The module according to claim 12 wherein the first retainerend portion is substantially perpendicular to the center portion. 19.The module according to claim 18 wherein the first retainer end portionis oriented at an angle of about 95 degrees relative to the centerportion.
 20. The module according to claim 12 wherein the secondretainer end portion is configured to engage the inflator near a top anda bottom of the second opening as the inflator is moved to a retainedposition and to be bent as the inflator is so positioned.
 21. An air bagmodule (20) comprising: an inflator (200) for providing inflation gas;the inflator having a first end, a second end and a body between thefirst and second ends; a retainer or bracket assembly (100) having acentral plate portion, a flexible first bracket (120) having a firstopening therein, a second bracket (130) oriented at an initial firstnon-perpendicular predetermined angle relative to the central plateportion, the second bracket having a second opening therein; when theinflator is in a mounted configuration upon the retainer or bracketassembly, the first end extends outward from the first bracket, thesecond end extends away from the second bracket and wherein the body isin direct contact with the second bracket, wherein the second bracket isconfigured as a spring and deformable by movement of the inflator bodyto the mounted configuration and the second bracket configured to createa twisting force upon the body of the inflator tending to hold the bodyin the retainer or bracket assembly.
 22. The air bag module according toclaim 21 wherein a portion of the second bracket, proximate a lowerportion of the second opening, is configured as a hinge about which theinflator can rotate as the inflator is moved to the mountedconfiguration upon the bracket assembly.
 23. The air bag moduleaccording to claim 22 wherein when the inflator is in a mountedconfiguration within the bracket assembly, a portion of the inflatorbody apart from that portion proximate the hinge is in contact with anupper portion of the second bracket, wherein the upper portion of theflexible bracket generates at least a portion of the twisting forceacting on the body.
 24. The air bag module according to claim 21 whereinthe body has a length and the bracket assembly has a length, wherein thelength of the body of the inflator is not restricted to be substantiallythe same value as the length of the bracket assembly.